1. Field of the Invention
The present invention relates to a coolant outlet element to be incorporated in the cooling system for an internal combustion engine, and more particularly to a coolant outlet element to which a plurality of temperature sensitive elements such as temperature sensors or temperature switches are to be attached.
2. Description of the Prior Art
In an internal combustion engine of a vehicle such as an automobile a plurality of temperature sensitive elements such as temperature switches and temperature sensors are provided at an intermediate portion of a coolant passage to detect the coolant temperature to obtain temperature parameters for various control operations such as fuel supply control, coolant fan control and exhaust gas purification control according to the temperature of the internal combustion engine and to indicate coolant temperature to the driver's seat. It has already been proposed to fit a plurality of such temperature sensitive elements as concentrated at a coolant outlet element, as described for example in Japanese Patent Publication Sho No. 61-38326 (1986).
The coolant outlet element has a coolant inlet port directly connected with a coolant extraction port provided in the internal combustion engine, a coolant outlet port directly or indirectly connected via a pipe line with a coolant pump, and a coolant passage extending between said coolant inlet port and said coolant outlet port, with a plurality of temperature sensitive elements being provided at an intermediate portion of said coolant passage.
However, if the coolant passage of the coolant outlet element is provided in a straight line form between the coolant inlet port and the coolant outlet port, then as the number of temperature sensitive elements to be attached increases, the coolant inlet port and coolant outlet port must be positioned largely apart from one another, and therefore the coolant outlet element has a long narrow shape. Therefore, depending on the type of the internal combustion engine, mounting conditions of the coolant outlet element in the vehicle, and/or the layout of the coolant pipe lines, such as long narrow coolant outlet element may be longer be appropriate. Further, when a coolant outlet element in which the coolant passage is provided has a straight line form, if the attachment apertures for the temperature sensitive elements are provided on the upper wall, side walls and bottom wall of the coolant outlet element in in order to make it as short as possible so that the orientation of the temperature sensitive elements varies according to the positions where they are fitted, the sensitivity to the coolant temperature of the different temperature sensitive devices becomes uneven, and the coolant temperature detection may become undesirably incorrect.